Describe giving reason which one of the following pairs has the proper – InterviewSolution

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1.	Describe giving reason which one of the following pairs has the property indicated? (a). `Fe` or `Cu` has higher melting point. (b). `Co^(2+)` or `Ni^(2+)` has lower magnetic moment.
Answer» (a). Fe has higher melting point than Cu. This is because Fe has four unpaired electrons in 3d-subshell while Cu has only one electron electron in the 4s-soubshell. Hence, metallic bonds in Fe are much stronger than those in Cu. (b). `Co(Z=27)implies3d^74s^2,Ni^(2+)=3d^8` (2 unpaired electron). Hence, Ni has lower magnetic moment than Co,

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